This application claims priority to German Application No. 102 06 091.6 filed Feb. 13, 2002.
1. Field of the Invention
The invention generally relates to a draft deflector for an opening in a roof of a motor vehicle. More particularly, this invention relates to a draft deflector comprised of a plurality of parts, which consist of different materials.
2. Description of the Related Art
Conventional sunroofs or moonroofs sometimes include draft deflectors that swing upwards out of a rest position into an operating position responsive to a spring force acting on them when the roof cover is opened. The function of draft deflectors is to reduce the wind noises occurring during travel with the roof cover entirely or partly open. The deflectors return to the rest position against the spring force when the cover is closed.
The wind force acting on the extended draft deflector during vehicle travel causes the deflector to vibrate. These vibrations may lead to disturbing draft deflector movements and, as a result, unwanted rattling noises if the swinging draft deflector strikes against fixed roof structure components. Rough driving conditions may also cause the draft deflector to vibrate in its rest position and strike against adjacent components with a rattling effect.
One draft deflector is shown in the German document DE 198 26 434 C1. The arrangement in that document provides a vibration-proof state of the draft deflector for the extended, operating position. A spring force and a toggle arrangement, which underpins the roof opening in a conventional manner and also supports the draft deflector by extension arms attached to the latter at the sides, reduce vibrations. A significant drawback, however is that the toggle arrangement is expensive and entails increased assembly expenses.
An example, known draft deflector is shown in DE 44 46 016 C1. That deflector is formed as a general-purpose base section comprising, for example, a light metal extruded section having a locating channel in which a rubber or plastics sealing section, which represents the rear region of the draft deflector body, is inserted. The sealing section is selected according to individual requirements to secure the most favorable shape from a group of differently shaped sealing sections. No measures are provided in the case of this known draft deflector to prevent unwanted rattling noises or vibrations in the operating position and the rest position.
There is a need for an improved draft deflector that reduces rattling and vibration. This invention provides a draft deflector that reduces noise-generating influences while avoiding the drawbacks of the prior art.
In general terms, this invention is a draft deflector for use with an opening in a vehicle roof. The inventive deflector has a deflector body comprising a dimensionally stable plastics base body and a flexible component secured to at least a portion of the base body. In one example, the flexible component is injection molded onto the base body to obtain a positive or adhesive bond. The inventive arrangement opens up the advantageous possibility of providing the flexible component at all locations of the base body where noise-reducing measures are recognized to be advantageous or expedient.
The flexible component in one example effectively attenuates impact and rattling noises when the deflector is in a rest position. In this example, portions of the flexible component protrude downwards at least partly beyond the base body. Such flexible component portions contact the front part of the roof frame from above when the deflector is in the rest position.
In another example, the wind noises arising due to turbulence during travel when the draft deflector is extended are attenuated by a flexible plastics element that preferably extends continuously over the length of the base body. The flexible element is injection molded onto the face which forms the top face of the base body in the operating position. In one example, the flexible element has a structured surface to influence the flow of air, across the deflector.
In another example, flexible plastics elements are injection molded onto the base body and protrude beyond the front edge of the base body. This example prevents the draft deflector from striking against the front wall of the front part of the roof frame with a rattling effect when the deflector is in the rest position.
One example embodiment has the forward protruding flexible plastics element formed essentially as a hollow section which extends continuously over the length of the base body and which closes the gap between the base body and the front edge of the roof opening in the extended operating position. This gap between the base body and the front edge of the roof opening (i.e., the bevel of the roof panel) is structurally inevitable, because on the one hand the draft deflector should not strike against the front edge of the roof opening and the front part of the roof frame when executing its swinging movements, and on the other hand manufacturing tolerances are to be compensated by the gap. When the draft deflector is in the operating position, the gap which is found in many known draft deflectors allows air to flow downwards through the gap and under the draft deflector during vehicle travel, which may entail substantial wind noises and play a part in making the draft deflector vibrate. Closing the gap when the draft deflector is in the operating position with elastic adaptation or deformation of the hollow section remedies such situations.
Flexible plastics elements in one example are injection molded onto the stops which limit the swing-out travel of the draft deflector. These flexible plastics elements, which effectively attenuate impact noises, may preferably be integrally injection molded with flexible plastics elements protruding downwards beyond the base body so that the stops mark both limit positions of the draft deflector to achieve low impact noise levels.
The base body in some examples preferably comprises a thermoplastic material reinforced with glass or carbon fibres and therefore has the required strength and dimensional stability. In another example, the base body is a cut-to-length extruded aluminium section.